The present invention relates to fast add-on memory for microcomputers.
Cache memory is a computer memory design concept which has been used for mainframe computers for several years. The concept is to have two separate memories for the same machine, a main memory which is large and medium speed and a cache memory which is small and fast. The software is loaded into the main memory and then sections of it are loaded into the cache memory as required for the central processing unit (CPU) to process. The purposes of this arrangement is to increase the processing speed of the computer without requiring the entire main memory to be of high-speed which can be very expensive. The cache memory in such mainframe computers are typically hard-wired into the computer and the internal CPU decides which operations should use cache memory and which operations should use the slower main memory.
Speed-up memory cards have been designed for microcomputers which have a high-speed processor and high-speed random access memory (RAM). Such cards have served to disable the processor in the microcomputer and replace the processor and RAM in the microcomputer with that on the memory card. However, the replacing of the entire memory with high-speed RAM can be very expensive due to the cost of such high-speed RAM.